A Technical Analysis of Ergonomics and Human Factors in Modern Flight Deck Design


I. Introduction
Since the dawn of the aviation era, cockpit design has become
increasingly complicated owing to the advent of new technologies enabling
aircraft to fly farther and faster more efficiently than ever before. With
greater workloads imposed on pilots as fleets modernize, the reality of he or
she exceeding the workload limit has become manifest. Because of the
unpredictable nature of man, this problem is impossible to eliminate completely.
However, the instances of occurrence can be drastically reduced by examining the
nature of man, how he operates in the cockpit, and what must be done by
engineers to design a system in which man and machine are ideally interfaced.
The latter point involves an in-depth analysis of system design with an emphasis
on human factors, biomechanics, cockpit controls, and display systems. By
analyzing these components of cockpit design, and determining which variables of
each will yield the lowest errors, a system can be designed in which the
Liveware-Hardware interface can promote safety and reduce mishap frequency.

II. The History Of Human Factors in Cockpit Design
The history of cockpit design can be traced as far back as the first
balloon flights, where a barometer was used to measure altitude. The Wright
brothers incorporated a string attached to the aircraft to indicate slips and
skids (Hawkins, 241). However, the first real efforts towards human factors
implementation in cockpit design began in the early 1930\'s. During this time,
the United States Postal Service began flying aircraft in all-weather missions
(Kane, 4:9). The greater reliance on instrumentation raised the question of
where to put each display and control. However, not much attention was being
focused on this area as engineers cared more about getting the instrument in the
cockpit, than about how it would interface with the pilot (Sanders & McCormick,
739).
In the mid- to late 1930\'s, the development of the first gyroscopic
instruments forced engineers to make their first major human factors-related
decision. Rudimentary situation indicators raised concern about whether the
displays should reflect the view as seen from inside the cockpit, having the
horizon move behind a fixed miniature airplane, or as it would be seen from
outside the aircraft. Until the end of World War I, aircraft were manufactured
using both types of display. This caused confusion among pilots who were
familiar with one type of display and were flying an aircraft with the other.
Several safety violations were observed because of this, none of which were
fatal (Fitts, 20-21).
Shortly after World War II, aircraft cockpits were standardized to the ‘
six-pack\' configuration. This was a collection of the six critical flight
instruments arranged in two rows of three directly in front of the pilot. In
clockwise order from the upper left, they were the airspeed indicator,
artificial horizon, altimeter, turn coordinator, heading indicator and vertical
speed indicator. This arrangement of instruments provided easy transition
training for pilots going from one aircraft to another. In addition, instrument
scanning was enhanced, because the instruments were strategically placed so the
pilot could reference each instrument against the artificial horizon in a hub
and spoke method (Fitts, 26-30).
Since then, the bulk of human interfacing with cockpit development has
been largely due to technological achievements. The dramatic increase in the
complexity of aircraft after the dawn of the jet age brought with it a greater
need than ever for automation that exceeded a simple autopilot. Human factors
studies in other industries, and within the military paved the way for some of
the most recent technological innovations such as the glass cockpit, Heads Up
Display (HUD), and other advanced panel displays. Although these systems are on
the cutting edge of technology, they too are susceptible to design problems,
some of which are responsible for the incidents and accidents mentioned earlier.
They will be discussed in further detail in another chapter (Hawkins, 249-54).

III. System Design
A design team should support the concept that the pilot\'s interface with
the system, including task needs, decision needs, feedback requirements, and
responsibilities, must be primary considerations for defining the system\'s
functions and logic, as opposed to the system concept coming first and the user
interface coming later, after the system\'s functionality is fully defined.
There are numerous examples where application of human-centered design
principles and processes could be better applied to improve the design process
and final product. Although manufacturers utilize human factors specialists to
varying degrees, they are typically brought into the design effort in limited
roles or late in the process, after the operational and functional requirements
have been defined (Sanders & McCormick, 727-8). When joining the design process
late, the